SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5e03da25ad740c415f48e3547866ac1040b987b6a746a5ab201b2abcbb155bbc' 
  AND token = 'FiwQ86/r+gBvQfuhxnyxoVUoSbCpd4Ven/7jkq+PGCY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}